Background This meta-analysis sought to evaluate the potential benefits and harms of laparoscopic gastrectomy with D2 lymphadenectomy for locally advanced gastric cancer versus open surgery. Methods A comprehensive search for randomized controlled studies that compared laparoscopic versus open gastrectomy with D2 lymphadenectomy for locally advanced gastric cancer published until December 31, 2018, was conducted. Operative outcomes, early postoperative outcomes, and long-term results were analyzed using a random effects model. Results Five randomized controlled trials containing a collective total of 2157 patients were included. In comparison with open surgery, laparoscopic gastrectomy for locally advanced gastric cancer showed similar risks of short-term mortality and serious adverse events within 30 days after surgery. Regarding intraoperative outcomes, operative time was increased for the laparoscopic approach, whereas the estimated intraoperative blood loss tended to be less. However, the amount of evidence was low for most outcomes. In addition, the results for the length of hospital stay and time to first flatus did not show statistically significant differences. The number of harvested lymph nodes and compliance with D2 lymphadenectomy did not significantly differ between the two groups, indicating oncological equivalence of both approaches. However, long-term oncological results could not be evaluated due to a lack of relevant data in four of the trials. Conclusion Laparoscopic gastrectomy with D2 lymphadenectomy can be performed with equivalent overall short-term morbidity and mortality versus the open approach for locally advanced gastric cancer. However, further well-designed randomized controlled trials are necessary to assess the possible advantages and risks of the laparoscopic approach as well as the long-term results. Electronic supplementary material The online version of this article (10.1186/s12957-019-1600-1) contains supplementary material, which is available to authorized users.

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a member of the TNF superfamily. TRAIL has historically been distinct from the Fas ligand and TNFα in terms of selective apoptosis induction in tumor cells and has a nearly non-existent systemic toxicity. Consequently, in the search for an ideal drug for tumor therapy, TRAIL rapidly drew interest, promising effective tumor control with minimal side effects. However, euphoria gave way to disillusionment as it turned out that carcinoma cells possess or can acquire resistance to TRAIL-induced apoptosis. Additionally, studies on models of inflammation and autoimmunity revealed that TRAIL can influence immune cells in many different ways. While TRAIL was initially found to be an important player in tumor defense by natural killer cells or cytotoxic T cells, additional effects of TRAIL on regulatory T cells and effector T cells, as well as on neutrophilic granulocytes and antigen-presenting cells, became focuses of interest. The tumor-promoting effects of these interactions become particularly important for consideration in cases where tumors are resistant to TRAIL-induced apoptosis. Consequently, murine models have shown that TRAIL can impair the tumor microenvironment toward a more immunosuppressive type, thereby promoting tumor growth. This review summarizes the current state of knowledge on TRAIL's interactions with the immune system in the context of cancer.

Mechanisms of lymph node invasion seem to play a prognostic role in pancreatic ductal adenocarcinoma (PDAC) after resection. However, the 8th edition of the TNM classification of the American Joint Committee on Cancer (AJCC) does not consider this. The aim of this study was to analyse the prognostic role of different mechanisms of lymph node invasion on PDAC. One hundred and twenty-two patients with resected PDAC were examined. We distinguished three groups: direct (per continuitatem, Nc) from the main tumour, metastasis (Nm) without any contact to the main tumour, and a mixed mechanism (Ncm). Afterwards, the prognostic power of the different groups was analysed concerning overall survival (OS). In total, 20 patients displayed direct lymph node invasion (Nc = 16.4%), 44 were classed as Nm (36.1%), and 21 were classed as Ncm (17.2%). The difference in OS was not statistically significant between N0 (no lymph node metastasis, n = 37) and Nc (p = 0.134), while Nm had worse OS than N0 (p < 0.001). Direct invasion alone had no statistically significant effect on OS (p = 0.885). Redefining the N0 stage by including Nc patients showed a more precise OS prediction among N stages (p = 0.001 vs. p = 0.002). Nc was more similar to N0 than to Nm; hence, we suggest a rethinking of TNM classification based on the mechanisms of lymph node metastases in PDAC. Overall, this novel classification is more precise.